The disclosure relates to a wireless power repeater.
A wireless power transmission or a wireless energy transfer refers to a technology of wirelessly transferring electric energy to desired devices. In the 1800's, an electric motor or a transformer employing the principle of electromagnetic induction has been extensively used and then a method for transmitting electrical energy by irradiating electromagnetic waves, such as radio waves or lasers, has been suggested. Actually, electrical toothbrushes or electrical razors, which are frequently used in daily life, are charged based on the principle of electromagnetic induction. Until now, the long-distance transmission using the magnetic induction, the resonance and the short-wavelength radio frequency has been used as the wireless energy transfer scheme.
Recently, among wireless power transmitting technologies, an energy transmitting scheme using resonance has been widely used.
Since an electric signal generated between the wireless power transmitter (or wireless power repeater) and the wireless power receiver is wirelessly transferred through coils in a wireless power transmitting system using resonance, a user may easily charge electronic appliances such as a portable device.
However, the wireless power transmitter (or wireless power repeater) generates a magnetic field even in a location where the wireless power receiver is not placed so that efficiency of power transmission is reduced.
Further, in the wireless power transmitting scheme using resonance, a magnetic field generated from a transmission side (or repeating side) may exert a bad influence upon human health.